Add Convert-mens.cpp to repository.
Add Convert-mens.cpp to repository.

craigsapp/humlib,craigsapp/minHumdrum,craigsapp/humlib,humdrum-tools/minHumdrum,humdrum-tools/minHumdrum,craigsapp/minHumdrum,craigsapp/minHumdrum,craigsapp/humlib,humdrum-tools/minHumdrum